Well, let's start...
The helmet is an Etchû zunari-kabuto. It's distinctive shape is typical for the Hosokawa clan. Also the hanpô, an Etchû-bô, fits with that. Attached to this type of zunari-kabuto is usually a shikoro without fukigaeshi, at which the lames are covered in thin leather (a technic called kawa-tsuzumi). Aditionally is the lowermost lame edged with a narrow leather band (kawa-fukurin). As evident in your case!
I will continue with sangu and dô later on...
Ok, the sangu.
The sangu consists of sleeves (kote), thigh protection (haidate) and shin protection (suneate). Since the latter is probably missing, one would have to speak of nigu here. Regardless, due to the style, kote, like haidate, can also be categorized as Etchû. In addition, all parts have the same base fabric (ieji) and thus forming an original set that belongs together.
So far so good, the cuirass, a Yokohagi nimai-dô, is a bit strange and needs more detailed considerations....tomorrow...